What's all this about?

On 26th June at Goodwood, Bonhams will auction a 1998 Mercedes-Benz CLK, which is expected to reach £1.4 to 1.8 million. If that sounds expensive it is because the car is one of the rare CLK GTR Roadsters, built to qualify for racing; a car that cost $1.5 million when new.

What's so special about it?

This car is one of six roadsters built and the only one to be finished in black; the roadster was based on the CLK GTR Coupé, of which only 25 were built. Mercedes owned this car until 2014, when it passed to its current owner and it is showing just eight kilometres on the odometer. It is described as 'effectively a new car'.

In 1996 Mercedes-Benz switched its motor sport efforts from touring cars to sports cars; the GT1 series required race cars to be based on production models, which meant a road-legal car had to be built and sold. Development work was undertaken by AMG with work starting in December 1996 and the first track outing in April 1997. The CLK GTR won five out of 11 rounds to take the 1997 GT Championship. Road cars were built in 1998 and 1999 with the coupé costing over $1 million, while the roadster was the most expensive production car ever.

What else is in the auction?

Two other entries in the Festival of Speed sale are expected to exceed £1.5 million. There's a 1935 Aston Martin Ulster competition car, which was one of the works entries at Le Mans and has been owned by the same family since 1969. There is also a 1961 Porsche RS61 Sports Racing Car owned by Sir Stirling Moss.